A nun is seen near an image of Jesus of Divine Mercy before Pope Francis’ arrival to visit the Divine Mercy Shrine in Lagiewniki, a suburb of Krakow, Poland, July 30. CNS photo/Paul Haring)

Catholic priests and nuns must renounce their personal interests and create a church that “goes into the world” with “living writers of the Gospel,” Pope Francis said.

“In our lives as priests and consecrated persons, we can often be tempted to remain enclosed, out of fear or convenience, within ourselves and in our surroundings,” the pontiff said July 30 during a Mass with Polish religious, priests, seminarians and bishops.

“Jesus directs us to a one-way street: that of going forth from ourselves,” he said. “It is a one-way trip, with no return ticket. It involves making an exodus from ourselves, losing our lives for his sake.”

Pope Francis was preaching at Krakow’s St. John Paul II Shrine on the fourth day of his visit to Poland for World Youth Day.

With a reliquary containing a vial of St. John Paul’s blood present in the sanctuary, Pope Francis told the clergy and religious their lives should be “marked by service and availability” with “no closed spaces or private property for our own use.”

Disciples, he said, “do not build on the shaky foundations of worldly power, or settle into the comforts that compromise evangelization. They do not waste time planning a secure future, lest they risk becoming isolated and gloomy, enclosed within the narrow walls of a joyless and desperate self-centeredness,” the pope continued.

True disciples “love to take risks and to set out, not limited to trails already blazed, but open and faithful to the paths pointed out by the Spirit,” he said.

“Jesus’ heart is won over by sincere openness, by hearts capable of acknowledging and grieving over their weakness, yet trusting that precisely there God’s mercy will be active,” Pope Francis said.

Those who truly consecrate themselves to Jesus, draw life from the experience of forgiveness and “pour it out with compassion on our brothers and sisters,” he said. “Jesus wants hearts that are open and tender toward the weak, never hearts that are hardened.”

In a country where more than 94 percent of the people describe themselves as Catholic and some 39 percent attend weekly Mass, Pope Francis insisted the Gospel story of God’s mercy is still being written.

Catholic priests and nuns should strive to overcome any “resistance and weariness” and be “living writers of the Gospel,” he said. They must “take concrete care of the wounds of Jesus in our brothers and sisters in need, those close at hand and those far away, the sick and the migrant, because by serving those who suffer we honor the flesh of Christ.”

The Mass, which began 30 minutes earlier than planned because of the pope’s early arrival, followed his morning visit to the tomb of St. Faustina Kowalska at the nearby Divine Mercy basilica in Krakow’s Lagiewniki suburb.

Waiting for the pope in the basilica, the Sisters of Our Lady of Mercy gathered to pray the rosary in the chapel that houses St. Faustina’s tomb.

The solemn atmosphere became more upbeat as they began to rehearse their welcoming song for Pope Francis. They sang in Spanish, “Alabare” (“I will praise”), a popular Latin American church hymn in honor of the pope.

Excitement grew to a fever pitch as security guards and the papal entourage entered, signaling the pope’s arrival. The nuns sang louder and waved small flags emblazoned with the Vatican coat of arms and the World Youth Day logo.

Pope Francis greeted the nuns as he walked down the center aisle, making his way toward St. Faustina’s tomb, where he stood in prayer for several minutes.

He was then led to small table where he signed a visitor’s book with a citation from the Bible: “I desire mercy, not sacrifices.”

The sisters presented the pope with a replica of the famed image of Divine Mercy. The painting of Jesus with white and red lights emanating from his heart is one of two images commissioned by St. Faustina following her visions of Christ.

The pope gently touched the image and reverently kissed it, thanking the nuns for their gift. After departing the chapel, he boarded the popemobile to make his next stop at the Shrine of the Divine Mercy.

As the popemobile made its way, a throng of nuns chased after him while waving their flags. One smiling nun ran after the pope while playing her dark blue guitar and singing “Alabare” at the same time.

Before entering through the Holy Door of the Divine Mercy Shrine, the pope greeted hundreds of people waiting outside hoping to catch a glimpse of him.

Speaking in Spanish, Pope Francis called on them to never be far from Jesus “even when we think we are the worst because of our sins and faults.”

“That is how he prefers us; that is how his mercy pours over us. Let us take advantage of this day so that we can receive all of Jesus’ mercy.”

Walking toward the shrine, the pope greeted two young girls, one of whom lost both her legs. Jesuit Father Federico Lombardi, Vatican spokesman, said the girl received two prosthetic legs thanks to a donation by Pope Francis.

Once inside the shrine, the pope walked toward the confessionals. He was handed a purple stole, which he kissed, and began hearing confessions. He offered the sacrament to eight people: five young women, two young men and a priest.

In a Catholic News Service interview after the Mass, Poland’s primate, Archbishop Wojciech Polak of Gniezno, said he believed the pope’s summons to clergy to be “living writers of the Gospel” represented a “theological novelty” in papal teaching.

The pope’s call for a church that “goes into the world” had given many Polish clergy “food for reflection,” the archbishop added, but it is unclear how long Poland’s Catholic Church can continue to send priests and priests to help abroad.

“We still have a large number of clergy working in other countries, and we’ve always been ready to meet the mission needs of fraternal churches,” said Archbishop Polak, whose Gniezno diocese sends up to 40 missionaries abroad annually.

“But vocations are falling in Poland now, and there are fewer clergy available now — although we’ll also seek to ensure our church doesn’t close in on itself,” he said.